Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
With the onset of September, the average high-temperature subtly recedes from August's warm 81.9°F (27.7°C) to a still moderately hot 76.1°F (24.5°C). In the month of September, Decatur City experiences an average low-temperature of 56.3°F (13.5°C).Humidity
In September, the average relative humidity is 77%.Rainfall
In Decatur City, in September, it is raining for 11.5 days, with typically 2.24" (57mm) of accumulated precipitation. Throughout the year, in Decatur City, there are 132.4 rainfall days, and 20.24" (514mm) of precipitation is accumulated.Snowfall
In Decatur City, snow does not fall in June through September.Daylight
In September, the average length of the day is 12h and 27min.On the first day of September, sunrise is at 6:43 am and sunset at 7:47 pm. On the last day of the month, sunrise is at 7:11 am and sunset at 6:58 pm CDT.
Sunshine
The average sunshine in September in Decatur City is 9.4h.UV index
The average daily maximum UV index in September in Decatur City is 4. A UV Index value of 3 to 5 symbolizes a moderate threat to health from unsafe exposure to UV radiation for average individuals.Note: In September, the maximum UV index of 4 transforms into these recommendations:
Be vigilant - Preventing sunburn is recommended. The Sun's most harmful UV rays are emitted around midday; avoid staying outdoors for long during this time. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes.
Frequently asked questions
What are September temperatures in Decatur City?
What is the average humidity in September in Decatur City?
How much does it rain in Decatur City in September?
When it does not snow in Decatur City?
Does it snow in Decatur City in September?
What is the average length of the day in September in Decatur City?
What time are sunrise and sunset in September in Decatur City?
How long on average sun shines in September in Decatur City?
What is the UV index intensity in September in Decatur City?
Average temperature in September
Decatur City, IA
- Average high temperature in September: 76.1°F
The warmest month (with the highest average high temperature) is July (83.5°F).
The month with the lowest average high temperature is January (30.6°F).
- Average low temperature in September: 56.3°F
The month with the highest average low temperature is July (66°F).
The coldest month (with the lowest average low temperature) is January (16.9°F).
Average pressure in September
Decatur City, IA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in September
Decatur City, IA
- Average wind speed in September: 7.9mph
The windiest months (with the highest average wind speed) are January, February and March (10.4mph).
The calmest months (with the lowest average wind speed) are July and August (6.9mph).
Average humidity in September
Decatur City, IA
- Average humidity in September: 77%
The month with the highest relative humidity is June (83%).
The month with the lowest relative humidity is October (72%).
Average rainfall in September
Decatur City, IA
- Average rainfall in September: 2.24"
The wettest month (with the highest rainfall) is June (3.43").
The driest months (with the least rainfall) are January and December (0.67").
Average rainfall days in September
Decatur City, IA
- Average rainfall days in September: 11.5 days
The month with the highest number of rainy days is June (17.3 days).
The month with the least rainy days is January (4.8 days).
Average snowfall in September
Decatur City, IA
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.72").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Decatur City, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (8.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Decatur City, IA
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 9h and 2min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).
Average sunshine days in September
Decatur City, IA
- Average sunshine days in September: 16 days
The month with the most sunshine days is December (20.3 days).
The month with the least sunshine days is June (8.9 days).
Average UV index in September
Decatur City, IA
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in September
Decatur City, IA
- Average cloud cover in September: 29
The month with the most cloud cover is January (Cloud cover 51).
The month with the least cloud cover is July (Cloud cover 28).
Average visibility in September
Decatur City, IA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Decatur City, Iowa, USA
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